U.S. scientists have shown that a type of light found in sunshine directly activates T cells, which are used by our bodies to kill diseases.
Researchers from Georgetown University Medical Centre isolated T cells in blood from humans and mice, then exposed them to blue light, one of the non-carcinogenic components of sunlight.
The blue light appeared to make the cells start producing hydrogen peroxide, which is the bleach-like chemical cells release at the site of infections in order to kill bacteria.
Scientists already knew that the production of hydrogen peroxide appears to make T cells move the sites of infections, but the new study makes clear that sunlight is probably what triggers the immune response, according to the study’s senior investigator Gerard Ahern.
“T cells, whether they are helper or killer, need to move to do their work, which is to get to the site of an infection and orchestrate a response," Ahern said. "This study shows that sunlight directly activates key immune cells by increasing their movement."
Ahern also added that blue light from the sun, or from special lamps, is safer than UV light, which can promote skin cancer and melanoma.
Ahern suggested that blue light therapy might be a beneficial option to help patients boost their immunity if it’s discovered that blue light T cell activation only has positive effects on the body.
It was also already understood that the body fights infections with vitamin D production that can be triggered by the sun, but the study’s lead researcher says the phenomenon the new research describes appears to be “completely separate.”
In fact, Ahern says he believes “some of the roles attributed to vitamin D on immunity may be due to this new mechanism.”
The research is published Tuesday in Scientific Reports.